388 



Scientific Proceedings, Royal Dublin Society. 



and an eudiometer, as shown in figs. 1 and 2. The pump was prepared for use 

 hy placing in the laboratory flask a small amount of water, acidulated with 

 sulphuric acid, and boiling this until the steam had driven most of the air 

 out of the flask. The flask was then raised, and the cork well forced into the 

 neck so as to make a vacuum-tight joint, this being ensured by placing a 

 little mercury in the annular space above the cork. The mercury pump was 

 then worked until no air could be detected after a full stroke of the pump, 



Fig. 2. — Eudiometer and Reagent Pipette. 



the water in the laboratory flask being kept boiling all the time, and cold 

 water running through the condenser. 



The water to be examined was then drawn into the pump through the 

 second capillary, the volume being noted by means of two marks on the 

 narrow necks of the bulbs, one at 50 cc, and the second at 250 cc. 



A. short length of thick-walled rubber tubing, one end of which had been 

 rounded by melting its edges in a bunsen flame, was slipped over the end of 



